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31.
The International Journal of Life Cycle Assessment - The present study assesses environmental performance of seafood production by demersal trawling in Tunisia (Gulf of Gabes) in order to analyze...  相似文献   
32.
Chickpea is the most cultivated grain legume in the world and it shares the first rank with faba bean in Tunisia. However, the yield remains low, mainly due to the limited availability of N and P, and to the severe bioclimatic conditions. No inoculation trials had been conducted on chickpea in the Tunisian soils. This paper reports the yield response to inoculation by two different strains of Mesorhizobium ciceri, an exogenous type strain (UPMCa7T) and a selected local strain (CMG6). Field experiments were conducted in different sites in the north of Tunisia using three chickpea cultivars (cvs. Amdoun I, Chetoui and Kasseb). Rhizobia occupying field nodules were isolated and identified using 16S rDNA typing for both inoculated and non-inoculated plots. In contrast to the exogenous strain, the local strain gave a significant increase in nodule number and shoot dry yield in all the experimental fields for the three cultivars used. Monitoring of the nodule occupancy showed that the local strain competed well the native populations of rhizobia. The usefulness and the persistence of this strain in the different soils where it was introduced will be assessed further during the next years.  相似文献   
33.
ABSTRACT: Background Tunisia is a North African country of 10 million inhabitants. The native background population is Berber. However, throughout its history, Tunisia has been the site of invasions and migratory waves of allogenic populations and ethnic groups such as Phoenicians, Romans, Vandals, Arabs, Ottomans and French. Like neighbouring and Middle Eastern countries, the Tunisian population shows a relatively high rate of consanguinity and endogamy that favor expression of recessive genetic disorders at relatively high rates. Many factors could contribute to the recurrence of monogenic morbid trait expression. Among them, founder mutations that arise in one ancestral individual and diffuse through generations in isolated communities. Method We report here on founder mutations in the Tunisian population by a systematic review of all available data from PubMed, other sources of the scientific literature as well as unpublished data from our research laboratory. Results We identified two different classes of founder mutations. The first includes founder mutations so far reported only among Tunisians that are responsible for 30 genetic diseases. The second group represents founder haplotypes described in 51 inherited conditions that occur among Tunisians and are also shared with other North African and Middle Eastern countries. Several heavily disabilitating diseases are caused by recessive founder mutations. They include, among others, neuromuscular diseases such as congenital muscular dystrophy and spastic paraglegia and also severe genodermatoses such as dystrophic epidermolysis bullosa and xeroderma pigmentosa. Conclusion This report provides informations on founder mutations for 73 genetic diseases either specific to Tunisians or shared by other populations. Taking into account the relatively high number and frequency of genetic diseases in the region and the limited resources, screening for these founder mutations should provide a rapid and cost effective tool for molecular diagnosis. Indeed, our report should help designing appropriate measures for carrier screening, better evaluation of diseases burden and setting up of preventive measures at the regional level.  相似文献   
34.
BACKGROUND: Metastases to the breast are rare and can be missed without knowledge of the clinical history. We report an unusual breast metastasis originating in an olfactory neuroblastoma. CASE: A breast metastasis from esthesioneuroblastoma occurred in a 20-year-old woman 2 years after the onset of the disease. The aspirates were hypercellular and composed of cellular aggregates and single cells with a monomorphic appearance. The cytoplasm was scanty and inconspicuous. The nucleus was large, with granular, hyperchromatic chromatin. Mitoses and apoptotic bodies were numerous. Because we were unaware of the past history at the time of the cytologic analysis, a definitive diagnosis was made only after pathologic study. CONCLUSION: Esthesioneuroblastoma metastatic to the breast must be considered in the differential diagnosis of breast metastases. Fine needle aspiration, in conjunction with clinical information, can be effective in the diagnosis of esthesioneuroblastoma metastatic to the breast.  相似文献   
35.
Thirty Pseudomonas spp. strains isolated from milk, water, cheese centre and cheese surface in two traditional workshops manufacturing raw milk St. Nectaire cheese were characterised by fluorescence spectroscopy and Biolog metabolic profiling. Factorial discriminant analysis (FDA) of the two data sets revealed clear linkages between groups of isolates. In the first workshop, milk could be incriminated as the sole source of cheese contamination. In the second one, milk and cheese centre isolates were found similar but surface cheese contaminants could be linked to a secondary contamination originating from water. Thus, it is possible to characterise, differentiate and trace Pseudomonas spp. strains using the fluorescence and metabolic profiling techniques. In addition, the two data sets were found highly correlated by canonical correlation analysis (CCA). Fluorescence spectroscopy however showed several advantages because of its low cost and processing speed.  相似文献   
36.
Comparing geographic variation of noncoding nuclear DNA polymorphisms, which presumably are neutral to natural selection, with geographic variation of allozymes is potentially a good way to detect the effects of selection on allozyme polymorphisms. A previous study of four anonymous nuclear markers in the American oyster, Crassostrea virginica, found dramatic differences in allele frequency between the Gulf of Mexico and the Atlantic Ocean. In contrast, 14 allozyme polymorphisms were fairly uniform in frequency between the two areas. This led to the conclusion that all of the allozyme polymorphisms were kept uniform in frequency by balancing selection. To test the robustness of this pattern, six additional anonymous nuclear DNA polymorphisms were surveyed in oysters from Panacea, Fla, and Charleston, S.C. on the Gulf and Atlantic coasts, respectively. Unlike the previously studied DNA markers, the six DNA polymorphisms examined here show geographic variation that is not significantly greater than that of allozymes. The reason for the discrepancy between the two sets of DNA polymorphisms is unclear.   相似文献   
37.
We report here the first complete mitochondria genome of Onchocerca volvulus from a focus outside of Africa. An O. volvulus mitogenome from the Brazilian Amazonia focus was obtained using a combination of high-throughput and Sanger sequencing technologies. Comparisons made between this mitochondrial genome and publicly available mitochondrial sequences identified 46 variant nucleotide positions and suggested that our Brazilian mitogenome is more closely related to Cameroon-origin mitochondria than West African-origin mitochondria. As well as providing insights into the origins of Latin American onchocerciasis, the Brazilian Amazonia focus mitogenome may also have value as an epidemiological resource.  相似文献   
38.
In wetlands the effects of fire on vegetation dynamics are somewhat uncertain. A change detection analysis in the herbaceous wetlands of KwaMbonambi, South Africa, which were subject to frequent fires, revealed that in 1937 the study area comprised grassland (69%), herbaceous wetland (25%), indigenous swamp forest (4%) and tree plantations (1%). However, by 1970, tree plantations occupied 78% of the landscape and grasslands and herbaceous wetlands had declined to 9% and 6%, respectively, whereas indigenous swamp forest had increased to 6%. By 2009 tree plantations had been removed from the wetland areas. Despite this opportunity for herbaceous wetlands to recover their historical extent, they decreased to only 2%, mostly changing to indigenous swamp forest or to an herbaceous/fern (Stenochlaena tenuifolia)/woodland mosaic. Fire records showed suppression of fire to be an important contributing factor, particularly in wetlands that had been disturbed by tree plantations, although subsequently removed. A pilot burning experiment revealed that S. tenuifolia did not inhibit fire. It is therefore practicable to increase fire frequency to prevent the mosaic developing into forest. A conceptual model of the influence of fire regime on wetland vegetation type is presented and priorities for further research on wetlands and fire are recommended.  相似文献   
39.
The synthesis of 14-(aryl)-14H-naphto[2,1-b]pyrano[3,2-e][1,2,4]triazolo[1,5-c]pyrimidine-2-yl) acetamidoximes 2ae has been accomplished by reaction of 2-acetonitrile derivatives 1ae with hydroxylamine. Cyclocondensation reaction of precursors 2ae with some elctrophilic species such as ethylorthoformate, acetic anhydride, and methyl-acetoacetate provided the new oxadiazole derivatives 3ae, 4ae, and 5ae, respectively. On the other hand, the reaction of precursors 2ae with 2-chloropropanoyl chloride afforded the new acetimidamides 6ae which evolve under reflux of toluene to the new oxadiazoles 7ae. The synthetic compounds were screened for their anti-xanthine oxidase, anti-soybean lipoxygenase, and cytotoxic activities. Moderate to weak xanthine oxidase and soybean lipoxygenase inhibitions were obtained but significant cytotoxic activities were noted. The most cytotoxic activities were recorded mainly (i) 5a was the most active (IC50?=?4.0?μM) and selective against MCF-7 and (ii) 2a was cytotoxic against the four cell lines with selectivity for MCF-7 and OVCAR-3 (IC50?=?17 and 12?μM, respectively) while 2e is highly selective against OVCAR-3 (IC50?=?10?μM).  相似文献   
40.
Patella ferruginea is the most endangered endemic marine invertebrate of western Mediterranean rocky shores. From 2012 to 2015, we performed a census and an ecological study for this gastropod mollusc in the Zembra Archipelago National Park in Tunisia, where a large population still remains. In 1986, a total of 20,000 individuals were estimated, with 0.7?ind/m2, 4.4?cm adult mean size and low recruitment rate. In 2009, the estimated population reached 38,559 individuals with 2.65?ind/m2, 5.42?cm adult mean size and high recruitment rate. During the present work, 43,790 individuals were estimated in 2012, 27,359 in 2013, 33,170 in 2014 and 40,404 in 2015, with an average density ranging from 0.1 to 8.5 individuals per square metre, but reaching as many as 25?ind/m2 on some shores. This makes the archipelago one of the most important Mediterranean ‘hot spots’ for P. ferruginea, as it has a large and well-conserved population of this species. Variability of the population size is influenced by various biotic and abiotic factors, but is principally impacted by poaching of the species. The poachers target individuals larger than 6?cm in length, and the sex ratio study has shown that over 70% of individuals become females at that size. In addition, high recruitment rates were recorded in 2012 and 2013, but these decreased in 2014 and 2015, although population numbers show the opposite pattern. Moreover, growth rate is low and P. ferruginea may need many years to reach a large adult size. The loss of reproductive potential due to poaching inevitably causes a significant imbalance in the limpet population. Our results indicate the importance of the National Park for P. ferruginea and underline the need for this species to be protected and monitored over a long period to provide the most appropriate management measures.  相似文献   
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